2G Head on 6 Bolt block

[gbpkr]

What are the advantages of keep the 2g head when a 6 bolt block is swpped in? I know all the advantages of the 1g head as far as bigger ports, etc, but what are the benefits of keeping the 2g head? I have seen someplaces where it has been said that the motor runs better and the amount of CELs is low.

Anyone have any input/ experience?

 

[xinfiniter]

I had 6 bolt block with 2G head....then went 1G head along with tb and intake manifold and the car seems to like the 1G head a lot more! I would just go 1G head if you can get it.

 

[DSMRevolution]

There are no benifets basicually. The 2g head is always at a lesser advantage compaired to the 1g head. If you have a 1g head, use it. Just make sure not to put non turbo cams in a turbo head or vice versa. I am not for sure but I would think that turbo cams in a non turbo engine would perform better, but I am not sure.

 

[Mindslayer]

I did a ported and polished 2g head with 1g TB and intake and it's flows greats I'll do a portedout 2g head if you have te extra money and sporing and retainers and CAMS if you have the money.

 

[wicked93GS]

you'll be better off going with a 1g head if you can, ported an ploished preferrably, but just a regular 1g head if you cant and intake and TB, you'll be happier in the end, and it will save the expense and hassle of having to do it later, 2g heads flow like crap from what I have heard(unless they are ported and polished)

 

[brryder]

The only advantage I see when u keep the 2g head is that it makes the swap easier.

 

[rubbersidedown]

some seem to believe the 2g head gives a little more low end torque. its good if you do autocross

 

[Tevenor]

Don't forget that 7-bolt 2g motors use 11mm head hardware and 6-bolt motors use 12mm head headware.

 

[gbpkr]

I guess I'm not worried about the performance gains that the head would give me. I just want the car to run with the least amount of problems. The goals I have for the car are very modest anyway; I think a ported 1g head would be overkill for me.

 

[genxxxracer]

This might be a stupid question, but when I removed the head from my car the 10bolts holding it to the block required a 12mm 12point socket to remove them. Is this what you are referring to Tevenor. Just made me think I might have a 6bolt. Doubtful, but maybe.

 

[brryder]

i think they meant the width of the screw. One of them uses a 11mm and the other uses 12mm

 

[Tevenor]

Originally posted by brryder
i think they meant the width of the screw. One of them uses a 11mm and the other uses 12mm

I am talking thread size, not hex head size.

 

[treimche]

The only 2 advantages that I know of for putting a 2G head back on your car are:
1. Ease of installation. You won't need to change intake manifold, throttle body, coil packs and also the vaccum lines and wiring will all stay the same.
2. The 2G head actually is better for porting because there is so much more metal there to work with, that they can shape the ports exactly how they want them to be. But the drawback to that is it is always really expensive to do it that way. You can do just a basic port and polish and that will get that 2G head to flow as well as a stock 1G head.

So you could go either way. It all depends on what you really want. From the research I've done a stock 1G head (portwise) will flow enough to get your car into the 10s in the 1/4 (with the proper supporting mods of course ).

 

[genxxxracer]

If the bolts are different for 6bolt vs 7bolt. Will I have any problems putting the 1g head on my 7bolt 2g. I would still need the arp head studs for the 2g or 7bolt since they go in the block right? Also if the bolt holes are made for bigger studs will there be fitment issues as far as getting a proper seal. I really dont want to have to drill out the 7bolt to put the bigger studs in if I dont have to.

 

[Tevenor]

Originally posted by genxxxracer
If the bolts are different for 6bolt vs 7bolt. Will I have any problems putting the 1g head on my 7bolt 2g. I would still need the arp head studs for the 2g or 7bolt since they go in the block right? Also if the bolt holes are made for bigger studs will there be fitment issues as far as getting a proper seal. I really dont want to have to drill out the 7bolt to put the bigger studs in if I dont have to.

You won't have any problems fitting a 1G head onto a 2G block.

1) The 6-bolt 1G head has bigger head bolt/stud passages than is required.
2) The 7-bolt 1G head has the same size head bolt/stud passages as the 2G block so no problems there.
3) There are alignment dowels in the block that located the head for you. The head studs/bolts are there just to keep it down.
4) You always ALWAYS go with the hardware that fits the block. It's by far easier to clearance the passages than to retap the block.

 

[larryd]

Originally posted by gbpkr
I guess I'm not worried about the performance gains that the head would give me. I just want the car to run with the least amount of problems. The goals I have for the car are very modest anyway; I think a ported 1g head would be overkill for me.

Either head installed properly will not give you problems.

 

[NDgsx]

Just out of curiosity do ANY of you saying that a 1G head flows better than a 2G head have ANY flow bench numbers for them? Just curious.

Everyone seems to forget about this big piece of aluminum that bolts to a cylinder head, it's called an intake manifold. It's volume and much more importantly runner length play a large part in the powerband and volume of air flow.

CFM through ports isn't the end all determination of how well a head performs, there's port velocity also to be considered. Flow bench numbers DO not account for that.
Some heads that make great flow numbers on a bench produce crappy results.